Search for the decay mode $B^0\to pp\bar{p}\bar{p}$

A search is presented for the four-body decay $B^0\rightarrow p p \bar{p} \bar{p}$inasampleof$471$million$B\bar{B}$ pairs collected with the BaBar detector, operated at the SLAC PEP-II asymmetric-energy $e^{+}{e}^{-}$ collider. The center-of-mass energy is $10.58$ GeV. From a fit to the distribution of the energy-substituted mass $m_{\mathrm{E}\mathrm{S}}$, the result $$\mathcal{B}$(B^0\rightarrow p p \bar{p} \bar{p})=(1.1 \pm 0.5 \pm 0.2) \times 10^{-7}$ is extracted, where the first uncertainty is statistical and the second is systematic. The significance of the signal is $2.9$ standard deviations. The upper limit on the branching fraction is determined to be $2.0 \times 10^{-7}$at$90%$ confidence level.